The Montana Jack rigid scaler features a heavier sickle blade and more rigid shank for more tenacious calculus and for cement removal while maintaining a perfect contra angle for the most universal adaptation of all sickle scalers. PDT instruments are ideally weighted, featuring the most ergonomic handle with knurling to the instrument shank to provide increased comfort with less hand fatigue and pinch. PDT's focus on ergonomics greatly reduces the development of musculoskeletal disorders.